Jump to content
SAU Community

Recommended Posts

Hey guys,

I've recently manual swapped my RB25DE Skyline and have put a RB20E gearbox in. 

The RB20E gearbox is out of a series 1 R33 and my R33 is a series 2.

Since doing the swap, I've noticed my speedo is reading just over double and the odometer is rolling the ks over faster. I have kept the original auto cluster in for now untill I can source a manual one.

Could this be because of the transducer/speedo sensor? If so, which one would I need to get to get an accurate speed? An RB20E as this is what the gearbox is, or a RB25DE?

Or could the issue be something else entirely?

Cheers

13 minutes ago, GTSBoy said:

Surely they're the same skinny gearbox? Just put the sender from the original box into the new one?

The original one from the auto gearbox is bigger in diameter unfortunately. That was the first thing I checked out

39 minutes ago, GTSBoy said:

Ah sorry. I totally vagued on the point that it was a manual swap.

So yes, you just need the correct speed sensor to suit the dash. So skinny box sender. Probably the same S1/S2 anyway.

No worries. So do you reckon a RB25DE speed sensor would sort the speedo out? As there is already a RB20E speed sensor in the gearbox causing an inaccurate reading. Would a RB25DE speed sensor fit straight into a RB20E gearbox? Also, are maunal and auto speed sensors the same size?

4 hours ago, Tys_Skyline said:

Would a RB25DE speed sensor fit straight into a RB20E gearbox?

Well......you would have to hope so, otherwise your only fix is going to be electronic. That's doable, but, non-trivial. We can address that later, if need be.

The problem is that the speed sensor relies on 2 gears. One in the box, one on the end of the speed sensor. It would obviously be impossible for them to have 2 different gear ratios without BOTH gears being different. The fact that the error is exactly 50% (or 200%) of the expected/required reading would suggest that the difference is in the number of poles inside the senor. A 2 pole generator would produce half as many pulses per rev as a 4 pole generator. I'd be willing to bet that that's the difference. Problem is, I don't know that they actually did that.

Anyway, assuming that the difference is internal to the sensor, then the pinion gear on the two sensors should be the same and yes, either one would physically fit into either box and turn at the "right" speed.

20 minutes ago, robbo_rb180 said:

I've been using the Jaycar one in the stagea for more than 10 years, still working perfectly

TBH in my experience with the Jaycar module was a little different. I was using it in the middle of the car ECU to the cluster. It worked, but it only kicked in at about 30-40kmh. So anything under that would read 0kmh. It was also delayed. It may work for something int he same family that it just needs to do something like 'halve'

The dakota digital one worked perfectly in my application, and can be used for many, many, many different inputs and outputs.

  • 2 months later...

Just thought I'd post an update for anyone reading this thread in future that may have the same issue. I have the odometer reading correctly now after sourcing a series 2 speedo sensor (RB25DE) and putting it in the gearbox (RB20E). Cheers for all the imput guys 👍

  • Like 1
  • Thanks 1

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • The cross sectional area of a circular hole scales with the square of diameter. So a 2mm diameter hole is 4x the area of a 1mm hole. Not double. The 1.7mm hole is nearly 3x the area of a 1mm hole. You do not need restrictors at both ends of the oil supply line. If you have new, additional restrictors at the turbo end, that you did not have before, then you do not need a restrictor at the inlet end.
    • Hi all. Been a while but things are moving along. I just have something that I am wondering about. Since I will use OEM turbo oil pumbing, I got myself a new bolt, the one that goes into the engine block oil feed. As I recall (and see visually) this bolt comes restricted with I think a 1.7mm hole? Not quite sure but it was something around that size. The turbos have 1mm restrictor bolts installed, as necessary due to ball bearings and my higher oil pressures. Can I now just use that OEM bolt with the 1.7mm hole in for the engine block or will this actually be too much oil flow restriction and I have to drill it out first? In my head it would make sense for the bolt to be at least 2mm wide as both turbos take "1mm of oil flow". Do let me know if my logic is flawed here, I just want to make sure I don't kill my turbo bearings with too little oil. Don't know if I can trust the saying I read somewhere that ball bearing turbos essentially only need an oil mist
    • There are several aftermarket options available, from not-too-painful moneyhttps://justjap.com/collections/driveshafts-bearings/products/d-max-reinforced-replacement-rear-driveshaft-set-fits-nissan-s13-s14-s15-r32-r33-r34-c35 and  https://justjap.com/products/crank-motorsport-billet-rear-axles-fits-nissan-skyline-r33-gts-t-r34-gt-t?srsltid=AfmBOorQk4xkGUa98kO7v2ePLUiNt-HRrM2AwWNw9mbSIVE1ujBVwY__, all the way up to The Driveshaft Shop https://driveshaftshop.com/skyline-cv-axles/
    • Yeah based on old XRC5964S specs, it looks to be roughly GTX3576R sized? But this 5964S compressor will flow 90lb airflow somewhat similar to the compressors in both the GTX3584RS or G35-1050.. I fully expected the 0.64 rear A/R to choke up top - seems way too small from typical convention - but these are seemingly beneficial over the prior 0.82 results.. Be interesting to see if he comments on the EFR question in that thread - he mentioned in a prior video that BW EFR's were the "cats pajamas 10 years ago", but by the sounds of things all his kits have been using Xona for quite a while now.
    • Yeah it’s still got the oem manual gearbox and clutch, only kinda mods are a blow off valve, coil overs, and a aftermarket intercooler. Also had it for about 2 months now with a lovely midnight purple paint on it.
×
×
  • Create New...